Mash efficiency to good?

[sils13]

My question is. Is there an optimal mash efficiency for a home brewer? Obviously a 100% sounds awesome but is it really? Do u get some tannins and stuff that u don't want in your wort? Would like a 85-90% b better I was wondering if anyone had some info on this I didn't have much luck finding any info on this topic

 

[WoodlandBrew]

Tannis are produced by a combination of both high temperature and high pH. So if you are over sparing (runnings with 1.005 gravity or lower) with water that is too hot (170+) then it can be an issue.

To get higher efficiency you need to rinse more sugar out of the grain which takes more sparges. Also, the extra water going into your boil kettle means more boil down time. One or Two sparges should get you somewhere above 75% which is fine for most of us.

Every system has it's limits. Depending on the volume of your mash tun you may be able to get more sugar from less grain. See here:
http://woodlandbrew.blogspot.com/2012/12/when-more-grain-doesnt-add-more-sugar.html